Chino EH3000 Series, Инструкция по эксплуатации

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4. CONNECTIONS
4.4 Measuring Input Terminals
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(3) Connection of Thermocouples (TC) Input
Use a thermocouple wire (or compensation lead wire) to the input
terminals of this instrument. If a copper wire is used halfway, a
noticeable measuring error occurs.
Avoid using a pair of thermocouple wires in parallel with the other
instruments (controllers, etc.), otherwise troubles may occur
(Indication fluctuation, indication errors, and others may occur.).
If the instrument has the burnout function (optional), avoid using it in
parallel with other instruments (otherwise it may affect other
instruments).
(4) Connection of Resistance Thermometer (RTD)
Input
For preventing measuring errors, use a 3-core code of which each
wire has equal resistance value.
Avoid using one resistance thermometer in parallel with other
instruments (controllers, etc.).
3-core cord
(Same diameter and length)
Resistance thermometer
Note: The resistance value for one code is
10 Ω or less. Use 3 codes which have
the equal resistance value.
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Resistance thermometer (RTD) input
1 2 3 4 5 6
A
B
b
Channel
The input terminals arrangements for 1-, 2-, 3-point type
specification and pen type differ. Refer to the input terminals
diagram on the back of the instrument and (5) Measuring Input
Terminals Arrangement mentioned later.
Input Terminals for 1-, 2-, 3-point Types
If input is opened in the state of no burnout function,
indication/recording values become unstable.
Indication/recording may be placed in the lower limit position, or
in the higher limit position temporarily; however, that state is not
guaranteed.
Indication/recording on Input Open
Input terminals cover
Fixing screw
Fixing of the Input Terminals Cover
A high voltage may be applied to the measuring input
terminals due to common mode noise (common mode voltage
applied between the measuring input terminal and protective
conductor terminal). The tolerance of the common mode
voltage is 30VAC or 60VDC or less. Make sure that the
common mode voltage is lower than the tolerance.
Make sure to close and mount the terminal cover with a screw
after the connection for preventing an electric shock and
protection of input cables. Closing and mounting the terminal
cover allows reducing errors of reference junction
compensation.

-marking on Measuring Input Terminals
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Thermocouple (TC) input
Compensation
lead wire
Thermocouple
White (-)
1 2 3 4 5 6
Red (+)
Channel
For the terminals for DC voltage and thermocouple input,
channels are insulated (functional insulation, Note 3); however,
for the terminals for resistance thermometer, channels have
equal potential (All b terminals are connected within the
instrument.).
Note 3) Functional insulation: Insulation necessary for normal
operation of instruments without protective function against
electric shocks (avoiding ground loop formulation of
instruments)
Insulation between Channels of
Measuring Input Terminals